In recent years, in order to simplify the assembling procedure and automate the assembling operation of a car body, a headlamp unit, a front bumper and the like are sub-assembled to a radiator core support panel, thereby forming a so-called front end module, and the front end module is assembled to a front portion of the car body on an assembling line of car body (see Japanese Patent Application Laid-open Nos. H11-20543, H11-48856).